Diagnosis And Testing - Engine Block Heater

WARNING: This page is about a different car, the 2017 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

If the unit does not operate, possible causes can be either the power cord or the heater element. Test the power cord for continuity with a 110-volt voltmeter or 110-volt test light.
Test heater element continuity with an ohmmeter.

CAUTION:

To prevent damage, the power cord must be secured in its retainer clips and away from any components that may cause abrasion or damage, such as linkages, exhaust components, etc.